Resin fixings, a bit of help please

[footprints]

I am fixing a heavy canopy at home, the bricks are brittle and cracked with rawplug type fixings, so I went to chemical ones, but when drilling, the bricks tend to pop into the cavity as soon as the hole gets much deeper than 80mm or so no matter how carefully I drill.

The studs I intended to use are cut at 95mm so the answer seems to be the nylon sleeves for hollow fixings which will stop resin bleeding into the cavity, but there don't seem to be any 100mm+ sleeves around most seem to be 85mm or so.

The studs are m12 and as far as I can see the sleeves for this size seem to be 20mm across.
Is that the right size for m12 studs and why don't they seem to make deeper ones?

I did try pushing a piece of large wall plug through to try and seal the inner leaf but as the brick has burst on the inside the exit hole is oversized.

It has not been a good day, the drinks cupboard is looking more and more inviting sob, sob!

 

[footprints]

Hey-Ho finished up the Budweiser moved on to Doombar so things are looking better. Still hoping for a solution if not I guess it will be bodgeit time!

 

[cjard]

Try a tile drill bit for the last 20 mm? They're diamond coated ace of spades shaped things on the end of a stick, you don't use hammer mode so it might avoid blowing the brick

Perhaps you can use a similar method that we did for casting pad stones in place under a support lintel
Pound the entire brick out with a hammer
Cut a bit of 12 mm plywood the same height and slightly wider than the hole
Create a hopper shaped bit of ply using two triangles, and a rectangle, make it slightly higher than the hole and exactly as wide (distance between internal faces of triangle=hole width)
Attach the two together with a 150mm wood screw, the rectangle part being the inner
Slide the whole thing into place, put the inner wood in at an angle to start with then straighten it up and position over the hole
Pulling on the screw to provide friction and stop the inner bit turning, wind the screw up so your hole is now blocked on the back side and you have a hopper on the front side
Trowel a fairly runny concrete mix in til the entire hole is full and the concrete level in the hopper is a bit higher than the top of the hole, then use an sds hammer drip in vibrate only mode on the hopper wood, vibrating the concrete to settle it
Leave it to set but not go rock hard
Remove the hopper and flatten the face concrete off while it's still green and easy to shape
Let it cure then fit your fixings
You might even be able to work out a way to cast the concrete around the fixing, if it's like a big rawlplug



Personally, I'd use different fixings I think.. some concrete screws and a 6mm drill bit, you don't really care if the back of the brick blows off, as you'll still have80mm of it to fix to and most of the load of the canopy is not going to act so as to pull the fixings out of the wall. If this wall is external, drill at a slight upwards angle

 

[footprints]

Thanks for your detailed reply cjard.
I like the idea of trying a tile drill, Screwfix have a 12mm diamond tile drill, not quite sure of the length it says 8mm but that can't be right guessing it is a misprint and is in cm, I have one on click and collect for later today.
With luck by only putting part way into the chuck I can get the depth I need.
I do hope I don't need to hack out bricks, I can see how you cast your pads and that might well be an answer, maybe even replacing the inner wood with a sheet of thin alli backed with some strap iron and bolted through like a megga toggle bolt!
Looks really yuck out there today, so may leave it a day or two before doing battle again

Cheers,
footprints

 

[footprints]

Try a tile drill bit for the last 20 mm? They're diamond coated ace of spades shaped things on the end of a stick, you don't use hammer mode so it might avoid blowing the brick

Perhaps you can use a similar method that we did for casting pad stones in place under a support lintel
Pound the entire brick out with a hammer
Cut a bit of 12 mm plywood the same height and slightly wider than the hole
Create a hopper shaped bit of ply using two triangles, and a rectangle, make it slightly higher than the hole and exactly as wide (distance between internal faces of triangle=hole width)
Attach the two together with a 150mm wood screw, the rectangle part being the inner
Slide the whole thing into place, put the inner wood in at an angle to start with then straighten it up and position over the hole
Pulling on the screw to provide friction and stop the inner bit turning, wind the screw up so your hole is now blocked on the back side and you have a hopper on the front side
Trowel a fairly runny concrete mix in til the entire hole is full and the concrete level in the hopper is a bit higher than the top of the hole, then use an sds hammer drip in vibrate only mode on the hopper wood, vibrating the concrete to settle it
Leave it to set but not go rock hard
Remove the hopper and flatten the face concrete off while it's still green and easy to shape
Let it cure then fit your fixings
You might even be able to work out a way to cast the concrete around the fixing, if it's like a big rawlplug



Personally, I'd use different fixings I think.. some concrete screws and a 6mm drill bit, you don't really care if the back of the brick blows off, as you'll still have80mm of it to fix to and most of the load of the canopy is not going to act so as to pull the fixings out of the wall. If this wall is external, drill at a slight upwards angle

All done now thanks, the diamond drill worked well on all but one and I think I was a bit impatient with a hard bit of brick so popped it!
I realised I needed a 14mm drill which Screwfix do not sell finally, but managed to track down one on Amazon only short as it was for tiles though. Luckily I managed to find a bit of studding the same thread as the drill fitting internal thread so I screwed in in and locked a nut against it. I had to file the flats off to get the same dia as the 14mm bit. It then worked a treat!

Had to do a bit of bodging on the broken through ones I got hold of the smaller dia sleeves for 10mm stud which are 125mm long taped up the end that protruded into the cavity, cut some large slits down the sides to allow plenty of epoxy to flood out into the manky holes within the brick and pumped in masses of resin they seem to have gone off well.

Thanks again for your help